John K,
Yes, there will be a base plate to which the various rails will be riveted; this should help support the frog since the rails are light.
I still have to make one set of 35-pound switch points for one of the switches in the "south" yard, I believe into Bay 2 or 3, as the existing points are very short.
I could probably make the parts for a 60-pound frog but it would definitely be a lot of weight mounted off-center on the 8-foot bed of the milling machine. And bending the kinks in both the frog point and wing rails would require 3 people to support the rail and operate the hydraulic press. And there is the time factor and wear/tear on antique machines involved; if we can afford to buy switch parts at reasonable prices, does it make sense to spend limited volunteer hours making a lot of switch parts or spend that time making patterns or brake parts or assembling No. 9 or ...? Just my two cents.
Dave Wilson and Buster Hughes did the lion's share of the work on car 417; I installed the canvas roof and replacement roof walk back in the mid to late 80s, if I recall correctly.
Dave Crow